| dc.description.abstract | In this work we attempt to retake the theory of pressurized bearings, which main objective is to determine in an analytical-numerical way the key features of bearings which in turn will be important to predict the behavior of a rotor system with externally pressurized bearings like supports; we must stress that this work focuses on the analysis of long bearings because the short bearings was analyzed in previous works.
Is known that external pressurization is a artificially way change properties stiffness and damping but to understand this requires know internal behavior the rowlock hence the importance this work.
In chapter I It contains the introduction and historical passage of the rotodynamic and all progress today are shared, of the researching about pressurized bearings.
In chapter II presents the model of pressurization linear injection ports, starting from the deduction of Reynolds, which allows us to determine the pressure field within a journal bearing as a function of their movement, in turn the transformation to cylindrical coordinates that for this particular case it becomes essential. Also we stress the classic models of journal bearings and shows the way to solving the proposed model using the Dirac spatial delta function, for the final shows the model for a long journal bearing with a pressurization line.
Chapter III presents the solution to the model that was set in the previous chapter, giving way first to a solution of the classical model (pressurization in a hydrodynamic bearing), taking into consideration the three possible solutions, Sommerfeld solution, solution Gümbel and Warner's theory, followed by external pressurization solution being proposed in this work, the pressurization is provided in the top or bottom of the bearing, taking these two solutions we can shows the total pressure fields (sum of two pressures: external and hydrodynamic) of a long hybrid bearing.
In Chapter IV frames the way to characterize a long hybrid bearing through the called Sommerfeld number or dimensionless load is used for the design of bearings and said that if the Sommerfeld number increases, the load carrying capacity decreases and vice versa, here also shows the relationship between the number of Sommerfeld with respect to an eccentricity at a given pressure, reaching if the final results depending on the solution of hydrodynamic pressure taken. These proposed solutions are intended to give a better understanding of operation to long bearings and help to design it.
Finally, we present the conclusions of the work and future work is expected as a follow up to this study and previous ones, highlighting areas for improvement and what is needed to raise a claim as proposed. | |
